AnnexGroup

AnnexSERVER · AnnexGroup

The groupware server
you own.

Mail, calendar, contacts, tasks and notes — in a single binary, on your own hardware. With AI assistants whose data never leaves the building.

Full feature set, no registration, no payment details.

Three differences that matter

One file, not a project

A single server process with built-in SMTP, IMAP and web interface. Not a dozen services somebody has to orchestrate first.

macOS and Linux as equals

The same codebase for Apple Silicon, Intel Macs and Linux on x86-64 and ARM. Not a second-class port — an equal target.

AI agents in your own house

Every user can create sub-accounts for assistants — with autonomy levels, an incubation period and approval before anything is sent. How it works

Why now

For self-hosted servers, several things have started to slide at once. The dates are fixed:

What When Consequence for self-hosting
Exchange Server 2016 and 2019 Support ended 2025-10-14 Its successor Exchange SE is a subscription; server and access licences went up by 10–20 %.
Kopano Groupware Ended 2025-03-31 Subscriptions cannot be renewed; the successor is a hosting-only offering.
Zimbra 9 OSE Ended 2025-06-30 Community builds only.
EWS in Exchange Online Shutdown starts 2026-10-01 The successor, Microsoft Graph, exists exclusively in the cloud. There is no replacement for self-hosting.

On top of that, prices are moving the other way: Microsoft 365 Business Standard rises from $12.50 to $14 per user and month on 2026-07-01, with Copilot at $21–30 extra. Google Workspace raised prices by 16–22 % in 2025.

What this means for your installation →

What is inside

Mail

SMTP and IMAP with STARTTLS, a queue with retries, DKIM signing, suggestions for SPF, DMARC and MTA-STS records, Sieve filters, Rspamd and ClamAV integration, out-of-office replies and signatures.

Groupware

Calendars with invitations, contacts with vCard import and export, tasks, notes, shared spaces for teams, sharing between users, colour-coded categories, full-text search across everything.

Devices and clients

CalDAV and CardDAV for iPhone, iPad and Mac. A web interface for every browser, installable as a web app. IMAP for any mail client you already use. OAuth2 and API keys for your own integrations.

Administration

Setup wizard, domain and user management, self-check with a traffic-light display, login-attempt protection, blocklists, backup and restore, certificates via Let’s Encrypt or your own.

What you pay

Buy once, use indefinitely — including all updates up to version 2.0. No access licences, no annual renewal, no price changes during operation.

An office with 25 workplaces pays €495 once under the introductory offer — net of VAT.

Frankly speaking

AnnexGroup is young. It does not replace every feature Exchange has accumulated over twenty years — it speaks neither MAPI nor ActiveSync; Outlook connects via IMAP and CalDAV. We put that here and not in the fine print, so you know before downloading, not after.

Everything it does, you can try in full for 14 days — without registration and without payment details.